1) Portal to an abandoned world. Will we see cthonic horrors? Or just very ancient things?
2) It's a familiar: maybe the new clan has not a bonus of its own but will be familiars giving extra bonus to all cards of a specific clan. Or go with any clan and take THAT bonus as their own
3) AD+D Persiflage characters
4) or I am just making all that up.
5) yes, there is a number 5 in the three options. Just because.